Part 5

The English figured greater windage was both convenient and economical: windage, said they, ought to be just as thick as the metal in the gunner's ladle; standing shot stuck in the bore and unless it could be loosened with the ladle, had to be fired away and lost. John Müller brushed aside such arguments impatiently. With a proper wad over the shot, no dust or dirt could get in; and when the muzzle was lowered, said Müller, the shot "will roll out of course." Besides, compared with increased accuracy, the loss of a shot was trifling. Furthermore, with less room for the shot to bounce around the bore, the cannon would "not be spoiled so soon." Müller set the ratio of shot to caliber as 24:25.

_Calibers and lengths of principal eighteenth century English cannon_

+-----------+---------------------+-----------+----------+ Caliber | Field | Ship | Siege | Garrison | +-----------+----------+----------+-----------+----------+ | Iron | Bronze | Iron | Bronze | Iron | +-----+-----+----+-----+-----+----+-----+-----+----+-----+ (pounder)| Old | New | Old| New | Old | New| Old | New | Old| New | ---------+-----+-----+----+-----+-----+----+-----+-----+----+-----+ 1-1/2 | | | | | | | 6'0"| | | | 3 |3'6" |3'3" | |3'6" | 4'6"|3'6"| 7'0"| |4'6"| 4'2"| 4 | | | | | 6'0"| | | | | | 6 |4'6" |4'1" |8'0"|4'4" | 7'0"|4'4"| 8'0"| |6'6"| 5'3"| 9 | |4'8" | |5'0" | 7'0"|5'0"| 9'0"| |7'0"| 6'0"| 12 |5'0" |5'1" |9'0"|5'6" | 9'0"|5'6"| 9'0"| 6'7"|8'0"| 6'7"| 18 | |5'10"| |6'4" | 9'0"|6'4"| 9'6"| 8'4"|9'0"| 7'6"| 24 |5'6" |6'5" |9'6"|7'0" | 9'0"|7'0"| 9'6"| 8'4"|9'0"| 8'4"| 32 | | | |7'6" | 9'6"|7'6"|10'0"| 9'2"|9'6"| 9'2"| 36 | | | |7'10"| | | | 9'6"| | | 42 | | |9'6"|8'4" |10'0"|8'4"| 9'6"|10'0"| |10'0"| 48 | | | |8'6" | |8'6"| |10'6"| | | ---------+-----+-----+----+-----+-----+----+-----+-----+----+-----+

In the 1700's cast-iron guns became the principal artillery afloat and ashore, yet cast bronze was superior in withstanding the stresses of firing. Because of its toughness, less metal was needed in a bronze gun than in a cast-iron one, so in spite of the fact that bronze is about 20 percent heavier than iron, the bronze piece was usually the lighter of the two. For "position" guns in permanent fortifications where weight was no disadvantage, iron reigned supreme until the advent of steel guns. But non-rusting bronze was always preferable aboard ship or in seacoast forts.

Müller strongly advocated bronze for ship guns. "Notwithstanding all the precautions that can be taken to make iron Guns of a sufficient strength," he said, "yet accidents will sometimes happen, either by the mismanagement of the sailors, or by frosty weather, which renders iron very brittle." A bronze 24-pounder cost £156, compared with £75 for the iron piece, but the initial saving was offset when the gun wore out. The iron gun was then good for nothing except scrap at a farthing per pound, while the bronze cannon could be recast "as often as you please."

In 1740, Maritz of Switzerland made an outstanding contribution to the technique of ordnance manufacture. Instead of hollow casting (that is, forming the bore by casting the gun around a core), Maritz cast the gun solid, then drilled the bore, thus improving its uniformity. But although the bore might be drilled quite smooth, the outside of a cast-iron gun was always rough. Bronze cannon, however, could be put in the lathes to true up even the exterior. While after 1750 the foundries seldom turned out bronze pieces as ornate as the Renaissance culverins, a few decorations remained and many guns were still personalized with names in raised letters on the gun. Castillo de San Marcos has a 4-pounder "San Marcos," and, indeed, saints' names were not uncommon on Spanish ordnance. Other typical names were _El Espanto_ (The Terror), _El Destrozo_ (The Destroyer), _Generoso_ (Generous), _El Toro_ (The Bull), and _El Belicoso_ (The Quarrelsome One).

In some instances, decoration was useful. The French, for instance, at one time used different shapes of cascabels to denote certain calibers; and even a fancy cascabel shaped like a lion's head was always a handy place for anchoring breeching tackle or maneuvering lines. The dolphins or handles atop bronze guns were never merely ornaments. Usually they were at the balance point of the gun; tackle run through them and hooked to the big tripod or "gin" lifted the cannon from its carriage.

GARRISON AND SHIP GUNS

Cannon for permanent fortifications were of various sizes and calibers, depending upon the terrain that had to be defended. At Castillo de San Marcos, for instance, the strongest armament was on the water front; lighter guns were on the land sector, an area naturally protected by the difficult terrain existing in the colonial period.

Before the Castillo was completed, guns were mounted only in the bastions or projecting corners of the fort. A 1683 inventory clearly shows that heaviest guns were in the San Agustín, or southeastern bastion, commanding not only the harbor and its entrance but the town of St. Augustine as well San Pablo, the northwestern bastion, overlooked the land approach to the Castillo and the town gate; and, though its armament was lighter, it was almost as numerous as that in San Agustín. Bastion San Pedro to the southwest was within the town limits, and its few light guns were a reserve for San Pablo. The watchtower bastion of San Carlos overlooked the northern marshland and the harbor; its armament was likewise small. The following list details the variety and location of the ordnance:

_Cannon mounted at Castillo de San Marcos in 1683_

Location No. Caliber Class Metal Remarks

In the bastion of San Agustín 1 40-pounder Cannon Bronze Carriage battered. 1 18-pounder do do New carriage. 2 16-pounder do Iron Old carriages, wheels bad. 1 12-pounder do Bronze New carriage. 1 12-pounder do Iron do. 1 8-pounder do Bronze Old carriage. 1 7-pounder do Iron Carriage bad. 1 4-pounder do do New carriage. 1 3-pounder do Bronze do.

In the bastion of San Pablo 1 16-pounder Demicannon Iron Old carriage. 1 10-pounder Demiculverin Bronze do. 2 9-pounder Cannon Iron do. 1 7-pounder Demiculverin Bronze do. 1 7-pounder Cannon Iron Carriage bad. 1 5-pounder do do New carriage.

In the bastion of San Pedro 1 9-pounder Cannon Iron Old carriage. 2 7-pounder do do Carriage bad. 2 5-pounder do do do. 1 4-pounder do Bronze Old carriage.

In the bastion of San Carlos 1 10-pounder Cannon Iron Old carriage. 1 5-pounder do do New carriage. 1 5-pounder do Bronze Good carriage. 1 2-pounder do Iron New carriage.

The total number of Castillo guns in service at this date was 27, but there were close to a dozen unmounted pieces on hand, including a pair of pedreros. The armament was gradually increased to 70-odd guns as construction work on the fort made additional space available, and as other factors warranted more ordnance. Below is a summary of Castillo armament through the years:

_Armament of Castillo de San Marcos, 1683-1834_

Kind 1683 1706 1740 1763 1765 1812 1834 of gun Iron Iron Iron Iron Iron Iron Iron Bronze Bronze Bronze Bronze Bronze Bronze Bronze

2-pounder 1 .. .. ** .. .. .. .. .. .. .. .. .. .. 3-pounder .. 1 .. ** 2 3 .. .. .. .. .. .. .. .. 4-pounder 1 1 * ** 5 1 .. .. .. .. 1 .. .. .. 5-pounder 4 1 * ** 15 1 .. .. .. .. .. .. .. .. 6-pounder .. .. * ** 5 .. .. .. .. 1 .. .. 3 .. 7-pounder 4 1 * ** 5 2 .. .. .. .. .. .. .. .. 8-pounder .. 1 * ** 11 1 5 11 .. .. 1 .. .. .. 3-1/2 in. carronade .. .. * ** .. .. .. .. .. .. 4 .. .. .. 9-pounder 3 .. * ** .. .. .. .. .. .. .. .. .. .. 10-pounder 1 1 * ** .. .. 6 .. .. .. .. .. .. .. 12-pounder 1 1 * ** .. .. 13 .. 7 .. 2 .. .. .. 15-pounder .. .. .. ** 6 .. .. .. .. .. .. .. .. .. 16-pounder 3 .. .. ** .. .. 2 1 .. .. 8 .. .. .. 18-pounder .. 1 .. .. 4 1 7 .. .. .. .. .. 4 .. 24-pounder .. .. .. .. 2 .. 7 .. 32 .. 10 .. 5 .. 33-pounder .. .. .. .. .. 1 .. .. .. .. .. .. .. .. 36-pounder .. .. .. 1 .. .. .. 1 .. .. .. .. .. .. 40-pounder .. 1 .. .. .. .. .. .. .. .. .. .. .. .. 24-pounder field howitzer .. .. .. .. .. .. .. .. .. .. .. .. 2 2 6-in. howitzer .. .. .. .. .. .. .. .. .. .. .. 2 .. 2 8-in. howitzer .. .. .. .. .. .. .. .. .. 2 .. .. .. .. Small mortar .. .. .. .. .. .. .. 18 .. 20 .. .. .. .. 6-in. mortar .. .. .. .. .. .. .. .. .. .. .. 1 .. 1 10-in. mortar .. .. .. .. .. .. .. .. .. .. .. .. .. 1 Large mortar .. .. .. .. .. .. .. 6 .. 1 .. .. .. .. Stone mortar 2 .. .. .. .. .. .. .. .. .. .. 3 .. ..

Total 20 9 26 9 55 10 40 37 39 24 26 8 14 6

Grand total 29 35 65 77 63 34 20

* 26 guns from 4- to 10-pounders

** 8 guns from 2- to 16-pounders

This tabulation reflects contemporary conditions quite clearly. The most serious invasions of Spanish Florida took place during the first half of the eighteenth century, precisely the time when the Castillo armament was strongest. While most of the guns were in battery condition, the table does have some pieces rated only fair and may also include a few unserviceables. Colonial isolation meant that ordnance often served longer than the normal 1,200-round life of an iron piece. A usual failure was the development of cracks around the vent or in the bore. Sometimes a muzzle blew off. The worst casualties of the 1702 siege came from the bursting of an iron 16-pounder which killed four and seriously wounded six men. At that period, incidentally, culverins were the only guns with the range to reach the harbor bar some 3,000 yards away.

Although when the Spanish left Florida to Britain in 1763 they took serviceable cannon with them, two guns at Castillo de San Marcos National Monument today appear to be seventeenth century Spanish pieces. Most of the 24- and 32-pounder garrison cannon, however, are English-founded, after the Armstrong specifications of the 1730's, and were part of the British armament during the 1760's. Amidst the general confusion and shipping troubles that attended the British evacuation in 1784, some ordnance seems to have been left behind, to remain part of the defenses until the cession to the United States in 1821.

The Castillo also has some interesting United States guns, including a pair of early 24-pounder iron field howitzers (c. 1777-1812). During the 1840's the United States modernized Castillo defenses by constructing a water battery in the moat behind the sea wall. Many of the guns for that battery are extant, including 8-inch Columbiads, 32-pounder cannon, 8-inch seacoast and garrison howitzers. St. Augustine's Plaza even boasts a converted 32-pounder rifle.

Garrison and ship carriages were far different from field, siege, and howitzer mounts, while mortar beds were in a separate class entirely. Basic proportions for the carriage were obtained by measuring (1) the distance from trunnion to base ring of the gun, (2) the diameter of the base ring, and (3) the diameter of the second reinforce ring. The result was a quadrilateral figure that served as a key in laying out the carriage to fit the gun. Cheeks, or side pieces, of the carriage were a caliber in thickness, so the bigger the gun, the more massive the mount.

A 24-pounder cheek would be made of timber about 6 inches thick. The Spaniards often used mahogany. At Jamestown, in the early 1600's, Capt. John Smith reported the mounting of seven "great pieces of ordnance upon new carriages of cedar," and the French colonials also used this material. British specifications in the mid-eighteenth century called for cheeks and transoms of dry elm, which was very pliable and not likely to split; but some carriages were made of young oak, and oak was standard for United States garrison carriages until it was replaced by wrought-iron after the Civil War.

For a four-wheeled English carriage of 1750, height of the cheek was 4-2/3 diameters of the shot, unless some change in height had to be made to fit a gun port or embrasure. To prevent cannon from pushing shutters open when the ship rolled in a storm, lower tier carriages let the muzzle of the gun, when fully elevated, butt against the sill over the gun port.

On the eighteenth century Spanish garrison carriage (fig. 28), no bolts were threaded; all were held either by a key run through a slot in the foot of the bolt, or by bradding the foot over a decorative washer. Compared with American mounts of the same type (figs. 30 and 31), the Spanish carriage was considerably more complicated, due partly to the greater amount of decorative ironwork and partly to the design of the wooden parts which, with their carefully worked mortises, required a craftsman's skill. The cheek of the Spanish carriage was a single great plank. English and American construction called for a built-up cheek of several planks, cleverly jogged or mortised together to prevent starting under the strain of firing.

Müller furnished specifications for building truck (four-wheeled) carriages for 3- to 42-pounders. Aboard ship, of course, the truck carriage was standard for almost everything except the little swivel guns and the mortars.

Carriage trucks (wheels), unless they were made of cast iron, had iron thimbles or bushings driven into the hole of the hub, and to save the wood of the axletree, the spindle on which the wheel revolved was partly protected by metal. The British put copper on the _bottom_ of the spindle; Spanish and French designers put copper on the _top_, then set iron "axletree bars" into the bottom. These bars strengthened the axletree and resisted wear at the spindle.

A 24-pounder fore truck was 18 inches in diameter. Rear trucks were 16 inches. The difference in size compensated for the slope in the gun platform or deck--a slope which helped to check recoil. Aboard ship, where recoil space was limited, the "kick" of the gun was checked by a heavy rope called a breeching, shackled to the side of the vessel (see fig. 11). Ship carriages of the two-or four-wheel type (fig. 31), were used through the War between the States, and there was no great change until the advent of automatic recoil mechanisms made a stationary mount possible.

With garrison carriages, however, changes came much earlier. In 1743, Fort William on the Georgia coast had a pair of 18-pounders mounted upon "curious moving Platforms" which were probably similar to the traversing platforms standardized by Gribeauval in the latter part of the century. United States forts of the early 1800's used casemate and barbette carriages (fig. 10) of the Gribeauval type, and the traversing platforms of these mounts made training (aiming the gun right or left) comparatively easy.

Training the old truck carriage had been heavy work for the handspikemen, who also helped to elevate or depress the gun. Maximum elevation or depression was about 15° each way--about the same as naval guns used during the Civil War. If one quoin was not enough to secure proper depression, a block or a second quoin was placed below the first. But before the gunner depressed a smoothbore below zero elevation, he had to put either a wad or a grommet over the ball to keep it from rolling out.

Ship and garrison cannon were not moved around on their carriages. If the gun had to be taken any distance, it was dismounted and chained under a sling wagon or on a "block carriage," the big wheels of which easily rolled over difficult terrain. It was not hard to dismount a gun: the keys locking the cap squares were removed, and then the gin was rigged and the gun hoisted clear of the carriage.

A typical garrison or ship cannon could fire any kind of projectile, but solid shot, hot shot, bombs, grape, and canister were in widest use. These guns were flat trajectory weapons, with a point-blank range of about 300 yards. They were effective--that is, fairly accurate--up to about half a mile, although the maximum range of guns like the Columbiad of the nineteenth century, when elevation was not restricted by gun port confines, approached the 4-mile range claimed by the Spanish for the sixteenth century culverin. The following ranges of United States ordnance in the 1800's are not far different from comparable guns of earlier date.

_Ranges of United States smoothbore garrison guns of 1861_

Caliber Elevation Range in yards

18-pounder siege and garrison 5° 0" 1,592 24-pounder siege and garrison 5° 0" 1,901 32-pounder seacoast 5° 0" 1,922 42-pounder seacoast 5° 0" 1,955 8-inch Columbiad 27°30" 4,812 10-inch Columbiad 39°15" 5,654 12-inch Columbiad 39° 0" 5,506

_Ranges of United States naval smoothbores of 1866_

Caliber Point-blank range Elevation Range in yards in yards 32-pounder of 42 cwt 313 5° 1,756 8-inch of 63 cwt 330 5° 1,770 IX-inch shell gun 350 15° 3,450 X-inch shell gun 340 11° 3,000 XI-inch shell gun 295 15° 2,650 XV-inch shell gun 300 7° 2,100

_Ranges of United States naval rifles in 1866_

Caliber Elevation Range in yards

20-pounder Parrott 15° 4,400 30-pounder Parrott 25° 6,700 100-pounder Parrott 25° 7,180

In accuracy and range the rifle of the 1860's far surpassed the smoothbores, but such tremendous advances were made in the next few decades with the introduction of new propellants and steel guns that the performances of the old rifles no longer seem remarkable. In the eighteenth century, a 24-pounder smoothbore could develop a muzzle velocity of about 1,700 feet per second. The 12-inch rifled cannon of the late 1800's had a muzzle velocity of 2,300 foot-seconds. In 1900, the Secretary of the Navy proudly reported that the new 12-inch guns for _Maine_-class battleships produced a muzzle velocity of 2,854 foot-seconds, using an 850-pound projectile and a charge of 360 pounds of smokeless powder. Such statistics elicit a chuckle from today's artilleryman.

SIEGE CANNON

Field counterpart of the garrison cannon was the siege gun--the "battering cannon" of the old days, mounted upon a two-wheeled siege or "traveling" carriage that could be moved about in field terrain. Whereas the purpose of the garrison cannon was to destroy the attacker and his matériel, the siege cannon was intended to destroy the fort. Calibers ranged from 3- to 42-pounders in eighteenth century English tables, but the 18- and 24-pounders seem to have been the most widely used for siege operations.

The siege carriage closely resembled the field gun carriage, but was much more massive, as may be seen from these comparative figures drawn from eighteenth century English specifications:

24-pounder 24-pounder field carriage siege carriage

9 feet long Length of cheek 13 feet. 4.5 inches Thickness of cheek 5.8 inches. 50 inches Wheel diameter 58 inches. 6x8x68 inches Axletree 7x9x81 inches.

Heavy siege guns were elevated with quoins, and elevation was restricted to 12° or less, which was about the same as United States siege carriages permitted in 1861. It was considered ample for these flat trajectory pieces.

Both field and siege carriages were pulled over long distances by lifting the trail to a horse-or ox-drawn limber; a hole in the trail transom seated on an iron bolt or pintle on the two-wheeled limber. Some late eighteenth century field and siege carriages had a second pair of trunnion holes a couple of feet back from the regular holes, and the cannon was shifted to the rear holes where the weight was better distributed for traveling. The United States siege carriage of the 1860's had no extra trunnion holes, but a "traveling bed" was provided where the gun was cradled in position 2 or 3 feet back of its firing position. A well-drilled gun crew could make the shift very rapidly, using a lifting jack, a few rollers, blocks, and chocks. When there was danger of straining or breaking the gun carriage, however, massive block carriages, sling carts, or wagons were used to carry the guns.

Sling wagons were of necessity used for transport in siege operations when the guns were to be mounted on barbette (traversing platform) carriages (fig. 10). Emplacing the barbette carriage called for construction of a massive, level subplatform, but it also eliminated the old need for the gunner to chalk the location of his wheels in order to return his gun to the proper firing position after each shot.

The Federal sieges of Forts Pulaski and Sumter were highly complicated engineering operations that involved landing tremendously heavy ordnance (the 300-pounder Parrott weighed 13 tons) through the surf, moving the big guns over very difficult terrain and, in some cases, building roads over the marshes and driving foundation piles for the gun emplacements.

The heavy caliber Parrotts trained on Fort Sumter were in batteries from 1,750 to 4,290 yards distant from their target. They were very accurate, but their endurance was an uncertain factor. The notorious "Swamp Angel," for instance, burst after 36 rounds.

FIELD CANNON